As sigkdtors to



RAYMOND C. BENNER AND HARRY F. FRENCH, OF FREMONT. OHIO. ASSIGNORS TO NATIONAL CARBON COMPANY, INC., A CORPORATION OF NEW YORK.

ELECTRIC BATTERY.

No Drawing.

To all tie/mm it may ('onccrn:

lie it known that we. hyuoxn BEN- xnu and HARRY I. FRHN citizens of the United States. and residents. respectively, of Fremont. in the county of Sandusky and State of Ohio. and Fremont. in the county of Sanduskv and State of Ohio. have invented a certain new and useful Improvement in Electric Batteries. of which the following is a full. clear. and exact description.

This inventionrelates to a process for making depolarizers for electric batteries.

In our application filed July 13, 1916. Serial No. 109.050. we disclosed the fact thatsulfur can be heated with copper oXid to form a solid block. the sulfur acting as the. binder. .\s disclosed in that application. the sulfur. in addition to the binding action. has the peculiar property of raising the voltage of the copperoxid cell.,that is. a cell having electrodes of zinc and copper oXid and an electrolyte of sodium h vdroxid or its equivalent. The melting point of sulfur is below 12-) and in the process de cribed in our prior application it was not heated higher than this temperature.

\Ye have discovered that the peculiar voltage raising propert of sulfur in the copper oxid cell is more prouoimced when the mix is heated at temperatures higher than this.

When sulfur and copper oxid are heated lng' 'illll' the raise in voltage increases with the temperature. until in the neighhmhood f Hi a maximum is reached which remains uh tautially constant up to a tempeiature of int! From 1st) to ahont 2314) the voltage effect f the sulfur decrea es lowly. but from then on it diminishes more rapidl nrtil at-IlHfi the etl'ect is practicall'v 1217'. That is. it copper oXid and ullur are h ated to 11. or higher. and placed as a derolarizer i= llt' alkaline cell referred to.

Specification of Letters Patent.

Patented Sept. 23, 19319.

Application filed March 30, 1918. Serial No. 225.693.

after being cooled to ordinary temperature. the voltage will not be much higher than if copper oxid alone had been used as a depolarizer.

o have also found that heating for a prolonged period at a certain temperature has somewhat the same effect as heating for a less time at a higher temperature.

'e. have obtained good results with as low as 1L2. of sulfur and have used as high as 402'; with substantially the same effect. in general. the best results are obtained by heating from 1 to sulfur with copper oxid for seven or eight hours at 1 A) (7. to one-half to one hour at L80 C. The mixture may be heated to temperatures be,- tween H and 150 with practicall maximum etfcct. and the time of heating would vary accordingly.

The time of heating required to secure maximum etl'ect will depend also upon the thoroughness with which the mixture is stirred. The more thorough the stirring. the less time required.

Having described our invention. what we claim is:

1. The proce s of making a battery depolarizer which consists in mixing copper oXid and sulfur and heating the mixture between 125" and 85 2. The process of making a battery depolarizer which consists in mixing copper oxid aml sulfur and heating the mixture, between ll and 1st) (1 3. batter le -rlarizer consisting of a mixture or copper oxnl and sulfur heated between 12-" and I183 t. and cooled to HUllllill fllltiillllilll't,

In testimony whereof. we hereunto at'lix our signatures.

HAYUUXI) t. KENNEL. HARRY i FRFNtl-l.

Copies ef this p' t may be obtained for live cents each, by addressing the "Commissioner of Patents, Washington, 3. 8. 

